There has been a long and intensive development of various methods and devices to determine the placement of upper and lower dentures and their relative positions in the patient's oral cavity, so as to restore a natural occlusion. This is evidenced by the large number of patents issued for this purpose over a lengthy period of time. The endeavor in this field has been to establish specific reference points relative to the positions of the teeth in the upper and lower jaws. These reference points establish exact positions of patterns for replacing natural teeth with dentures, whereby a natural bite or occlusion is restored.
Many of the devices described in prior art patents are too complex to be practical or do not provide the degree of accuracy required. A major shortcoming has been the inability to provide stable reference points which can be accurately ascertained, especially after all natural teeth have been extracted.
Ear openings with lip support have been used to establish reference points, for example, in U.S. Pat. Nos. 5,090,901 and 3,464,115. With these reference points, any particular position for the placement of dentures is difficult to reproduce, particularly in vertical spacing or dimensioning.
A frame supported on the patient's ears has been used for this purpose. The frame is a transverse rod supported on the bridge of a patient's nose. A lower frame is attached to the lower jaw and a stylus is used with a recording plate to obtain measurements. Such a device is so complex that its use is discouraged.
These and further examples of the prior art are found in U.S. Pat. Nos. 4,836,779; 4,695,252; 4,096,637; and 4,126,938.
The invention herein, as will be described, represents significant improvement and simplicity for establishing a natural bite in dentures.